Door operating mechanism



April 1957 J. J. LAW-ICK DOOR OPERATION MECHANISM 2 Sheeis-Sheet 1 Filed Aug. 50, 1954 3w. I i nj 4 INVENTOR.

J y w J W h w J. J. LAWICK DOOR OPERATION MECHANISM A ril 23, 1957 Filed Aug. 50, 1954 2 Sheets-Sheet 2 x V w I INVENTOR United States Patenr This inventionrelates to newanduseful improvements in door operatlng mechanisms, and has particular reference to an operating mechanism suitable for use in con- .nection with a vertically movable :door of the sectional type, such doors being commonly called overhead doors and incommon usage on garages and the like.

The principal object of the-present invention is the provision of a powered door operating mechanism of the class described having incorporated therein a-safety device whereby the closing movement of the door is arrested automatically in the eventany obstruction is interposed in thepath thereof, thereby preventing damage to anautomobile, or injury to a person,-that may-inadvertently be standing in the dooraopeningwhen the mechanism is actuated toclosethe door.

Another object is the provision ,of a-door operating mechanism incorporating thesafety-device as above described, wherein said safety device functions also as a limit control for shutting oh? the operation ofthe power unit when thedoor reaches its-normalopen and closed positions.

Other objects are simplicity and economy of construction, efiiciency and dependability of operation, and adaptability for use in connection with virtually any type of vertically moving door. Y

With these objects in View, as Well as other objects which will appear in the course of the specification, reference will be had to the drawing, wherein:

Fig. 1 is generally an inner face view of a doorshown in its closed position and having an operating mechanism embodying the present invention, being aisectionalv iew taken on line II of Fig. 2, with-parts broken away.

Fig. 2 is a sectional view taken online 11-11 of Fig. 1.

Fig.3 is an enlarged, ioreshortened, fragmentary view similar toFig. 1, showing the door raised slightly from closed position, and with parts broken away.

Fig. 4 is a fragmentary sectional view taken on line IV-IV of Fig. 3.

Fig. 5 is a fragmentary sectional view taken on line Y.V of Fig. 3,'with parts left inelevation.

Fig. 6 is a schematic Wiring diagram of the operating mechanism.

Like reference numerals apply to similar parts throughout. the several views, and the numeral 2 applies to the f door opening of a building wall 4', said door opening, being provided with a conventional vertically movable door 6 divided horizontally into a plurality of sections 8, 10, '12 and 14, said sections being pivotally joined together by hinges l6. Along its vertical side edges, said door is provided with a plurality of rol. :rs 18 which are engaged in guide tracks 26. Each track 20 has a vertical portion 22 aifixed to wall 4 by brackets 24 extending along one side of door opening 2, and a rearwardly extending horizontal portion 26 supported from the building ceiling'ZS by hangers 34), said horizontal and vertical portions being connected by a curved portion 32. In opening, the door moves upwardly and rearwardly, rollers 18 being guided sin tracks 20, until the door opening 2 is uncovered.

.bracketr54 fixed to the.uppermostdoonsection 8. 1 Thus -.-when motor 44is-operated=in onedirection cable. 34 will their; lower. ends to rod56, as at-fiil.

2,789,636 Ratented Apr, 23, 1957 -::The :door vis operated= by an. endless. cable 34 1 disposed by a reversible electrictmotor 44 mounted on ceiling'28. A link 46tis pivotedat .one end,-1as.at 48,10 a clamp 50 rigidly fixedaon cable'"34, .and is-pivoted 'as at:5.2'to a .move clamp 50 rearwardly,.pullingzrlink:46to open the door. wWhen! the .motorjis. operated in a reverse direc- @tion, the. action is. reversed .to closer the door.

.As'safety =rod 56* is disposed adjacent and parallel to .qthe inner-face ofthe'doorat the loweredge-of said door, .andis vertically movablenwith respect to the-door. -A

.pair-ofsupport.rods 58 areeach pivotally attached at Rod 56 extends substantially the fulltwidth ofthe door, and support rods :58iare disposed respectively in oppositely-spaced relation \fromthe'midpointof rod iSfi. .Rods 58 extends upwardly, and each is carried forzaxial sliding movement in holes -162'(Fig.4)- providedtherefor in a bracket 64; 'fixed to the inner surface of lowermostdoorsection 14 by screws 66. Rod 58 extends above bracket 64, and aunt 63- is iadjustably zthreaded thereon. to limit the downward moveunenb thereof. 'ir-when'thedoor is raised, rod 56-falls by gravity until nuts 68: strike-brackets 64, in which position 1rodr56 is. disposed below the lower edge 79 ofthe sdoor as shownzin Figsp i'a and 4. When the door-is lowered toitsxclosed position, rod 56 is raised relative .to thesdoor bynitssengagement with the floor 72- beneath the (10013110-a-pOSltlOBlflUSh with the loweredge -'.-'0 of theadoor, astshowninr Figs. l and 2. Rod 56 will also beraised as described-above if, during the closing movementofathe doorpit should strike a-person,-vehicle, or other obstructionflin itsapath. If theobstruction should beflofrlimited size, so-asforexample to engage-rod 56 adjacent one end-thereof, the rod -will tilt about one or the other. of pivots 60 of support rods 58. "For this-reason, the holes16t) of brackets 64 are made sufiiciently large to prevent binding of rods .58 therein.

A plurality of switch operating rods 74 are each pivot ally .-.attached at theirilower endsto rod 56, as-at 76. :Although the number of such rods is optional, there are three shown: in the 'drawing, one adjacent each end of rod .56 andone at the midpointthereof. "Each operating rod 74 extends; upwardly into. a switch housing 78 mountedon the inner surface of door section 14. Within saidhousing it extends. through. a hole 80 (Fig. 3 provided thereforin thefreeen-d portionofa tiltable switch support 82 which istpivotediimsaid housing at 84. Aanut fifitadjustably threadedon vrod-f74-serves to. engage and tilt saidswitch support upwardlywhensafety rod 56 is-raisedrelative to the door. Said switch support tilts downwardly-by gravity when thersafety rod=is lowered. -Suitably mounted on each switch support 82 is.a=tilt-responsive.- mercury switch, the three 1 switches being i designated respectively by the numerals 28S, S u-and: 92. -Said switches are -so disposed that they are closed-When'their supports 82 and safety rod 56 are lowered, and open when said supports and safety rod are raised. Carriedalso in-one -0f housing-"78, the central housing as shown, is a fourth tilt-responsive switch-94. Asshown in F igs.3 and- 5,-said switch isdisposed in an-inclined position 'in a verticalplane at right' angles to the plane of the door. Its inclination is' such that it will be closed when the door is in itsnorrnal vertical position, but will be tilted to open when the doorsect-ion 14 to whichit'is attachedis-tiltedoutofavertieal plan as the door is opened. Section 14 is the last section to be tilted toward a horizontal plane as the door opens. Switch 94 is carried by a bendable support 96 mounted in housing 78. By bending said support, the inclination of switch 94 may be adjusted, so as to vary the angle to which door section 14 must be tilted to open the switch.

Referring to Fig. 6, it will be seen that operating current for motor 44 is drawn from line wires 98 and 100 through wires 102 and 104 to a double-pole, double- .throw switch 106. Said switch is manually reversible to feed'current to motor 44 either through wires 108 and 110 to operate said motor in one direction to raise the door, or

through wires 112 and 114 to operate the motor in a reverse direction to lower the door. The internal wiring of the motor is conventional and is not here shown. Wire 102 is provided with a normally open push button switch 116, and wire 104 has a normally closed push button switch 118 therein. In a by-pass circuit around switch 116, there are connected in series a wire 120, switch 92, wire 122, switch 94, wire 124, switch 90, wire 126, switch 88, and wire 128. Thus all of the mercury switches 88, 90, 92 and 94 are connected in series to by-pass switch 116, or switch 116 may be said to bypass the mercury switches. The wires to the various tilt-responsive switches are disposed in conduits 130 suitably affixed to the inner surface of the door. The connections from the tilt-responsive switches to the motor and other stationary parts of the system are made through a flexible cable or other suitable means, not shown, which will not interfere with the movement of the door.

In operation, assuming that the door is closed as shown in Figs. 1 and 2, switch 94 will be closed, but switches 88, 90 and 92 will be open, due to the fact that safety rod 56 has been raised relative to the door by its contact with the floor. To raise the door, the operator first sets selector switch 106 to deliver current to the motor through wires 108 and 110, then closes switch 116 momentarily. This starts the door upwardly. As the door rises the first inch or two, safety rod 56 drops by gravity below the lower edge of the door, permitting switches 88, 90 and 92 to close. This completes the by-pass circuit around push button 116, and said push button may then be released. The door will then continue to rise until the lowermost section 14 thereof is tilted out of its normal vertical plane by the curved portions of tracks 20. This tilting action opens switch 94, thus interrupting the motor circuit and bringing the system to rest. At this time switches 88, 90 and 92 are closed, and switch 94 is open. To close the door, the operator first reverses the switch 106 to deliver current to the motor through wires 112 and 114, then depresses push button 116 momentarily. This completes the motor circuit, and the door starts downwardly. As soon as door section 14 is disposed vertically, or nearly so, switch 94is closed, thereby completing the by-pass circuit around switch 118, and switch 116 may then'be released. The door then normally continues its downward movement until safety rod 56 strikes floor 72 and is thereby raised I relative to the door to operate through control rods 74 to open switches 88, 90 and 92, thereby interrupting the motor circuit and bringing the system to rest. The over travel of the door, that is, the distance it will travel or coast after the current has been shut ofif, may be provided for by adjusting nuts 86 along rods 74 whereby to open switches 88, 90 and 92 before the door is completely closed. The over-travel will then carry the door to its completely closed position against the floor.

However, if during the closing motion of the door it should encounter an obstruction, such as a person standing in the door opening or a vehicle parked there, said ohstruction will be first engaged by safety rod 56, and said safety rod will be forced upwardly relative to the door. If the obstruction is of limited width as compared to the door, safety rod 56 will tilt relative to the door, on one or the other of pivots 60. In any event, however, at least one of switches 88, 90 or 92 will thereby be opened, interrupting the motor circuit and bringing the system to rest to prevent injury or damage to the obstruction. Push button 118 may be depressed at any time during the operation of the door, in order to stop the movement of the door whenever desired.

'It is apparent that if the safety rod 56 were perfectly rigid, only the switches 88 and 92 at the ends of said rod would be required, since no matter where an obstruction contacted the rod, one end of said rod would necessarily be raised; However, it is desirable that the safety rodbe small and light, and it of course must be substantially as long as the door is wide, which may be eight or ten feet in ordinary installations. Hence the rod is of necessity somewhat flexible, and might be flexed upwardly by an obstruction striking its mid-portion without raising its ends. For this reason the central switch 90 has been added. On very wide doors, additional intermediate switches might be required.

While I have shown and described a specific embodiment of my invention, it is apparent that many minor changes of structure and operation could be made without departing from the spirit of the invention as defined by the scope of the appended claims.

What I claim as new and desire to protect by Letters Patent is:

1. In combination with a vertically movable door, power means including a reversible electric motor operable to raise and lower said door, a plurality of vertical support rods disposed vertically and carried for limited axial sliding movement by said door adjacent the lower edge thereof, and adapted when in their lowermost position to depend by gravity below the lower edge of said door, a safety rod parallel to the lower edge of said door and extending substantially the full width thereof, each of said support rods being attached pivotally at its lower end to said safety rod on a horizontal axis at right angles to the plane of the door whereby to support said safety rod, a plurality of safety switches mounted on said door and connected in series in the operating circuit of said ,motor, and a plurality of operating rods each pivoted at its lower end to said safety rod on an axis parallel to the pivotal connections of said support rods and each operativelyconnected to one of said safety switches whereby to close said switch when said safety rod is lowered and to open said switch when said safety rod is raised.

2. A device as set forth in claim 1 wherein said safety switches are tilt-responsive and are pivotally carried by said door and normally urged toward their closed posi- ,tions by gravity, and wherein said operating rods function to tilt said switches to their open positions whenever said safety rod is raised relative to said door.

3. A device as set forth in claim 1 with the addition of a conductor lay-passing all of said safety switches in the motor operating circuit, and a starting switch in said conductor. i

4. In combination with a horizontally sectioned, normally vertical door which moves vertically to and from its closed position, and the sections of which successively tilt out of a vertical plane as said door is raised, power means including a reversible electric motor operable to raise and lower said door, and a tilt-responsive limit switch disposed inthe operating circuit of said motor and mounted on the lowermost section of said door, said switch being disposed to remain closed so long as said said safety member being adapted to depend below the lower edge of said door by gravity when said door is raised and to be moved upwardly relative to said door by engagement with the floor beneath said door as said door approaches its closed position, an operative connection between said safety member and said safety switch, whereby said switch is closed when said safety member is lowered and opened when said safety member is raised, and a tilt-responsive limit switch disposed in the operating circuit of said motor in series with said safety switch, and mounted on the lowermost section of said door, said switch being adapted to remain closed so long as said door section remains vertical, and to open when said door section tilts toward a horizontal plane.

6. A device as set forth in claim 5 with the addition of a conductor by-passing both the safety and limit switches in said motor circuit, and a starting switch in said conductor.

7. In combination with a vertically movable door, power means including a reversible electric motor operable to raise and lower said door, a plurality of safety switches mounted on said door in spaced relation adjacent the lower edge thereof, said switches all being connected in series in the operating circuit of said motor, a safety rod carried by said door parallel to the lower edge thereof and mounted for limited vertical and tilting movement with respect thereto, said safety rod being adapted to depend below the lower edge of said door by gravity when said door is raised and to be moved upwardly relative to said door by engagement with the floor beneath said door as said door approaches its closed position and an operative connection beneath said safety rod and each of said switches, whereby said switch is closed when said safety rod is lowered and opened when said safety rod is raised.

8. In combination with a vertically movable door, power means including a reversible electric motor operable to raise and lower said door, a tilt-responsive electric safety switch disposed in the operating circuit of said motor and pivotally mounted on said door, said switch being normally tiltable by gravity to a closed position, a rigid safety member carried by said door for limited vertical movement relative thereto, said safety member being adapted to depend below the lower edge of said door by gravity when said door is raised and to be moved upwardly relative to said door by engagement with the floor beneath said door as said door approaches its closed position, and an operative connection between said safety member and said safety switch and operable to tilt said switch to an open position as said safety member is raised relative to said door.

References Cited in the file of this patent UNITED STATES PATENTS 2,048,514 Peelle July 21, 1936 2,221,216 Greegor et a1 Nov. 12, 1940 2,401,082 Konter May 28, 1946 2,703,235 Reamey Mar. 1, 1955 

